Cha3topteriis Variopedatus. 495 



ate magnification. The presence of large globular goblet-cells con- 

 firms Benham's observation that the elongated ciliated cells which 

 contain the green granules are associated with gland cells. 



The pigment of the intestinal wall has received different names by 

 different workers ; Claparede calls it "hepatic" pigment, and Joyeux- 

 Laffuie designates the cells as "cellules biliaires." Lankester objects 

 to the above names. He introduced ('97) the name ''Chsetopterin" 

 for the fluorescent green pigment which is extracted from the intes- 

 tinal epithelium with alcohol. A comparison of its spectrum with 

 that of chlorophyll led him to correct an earlier statement and say 

 that it is not "chlorophylloid" (Sach's Botany, 2d ed. 1882) but, 

 like the green pigment, "Bonellin," of Bonellia viridis, a metabolic 

 product. He says (page 454), "It is impossible to suppose, in view 

 of the fact that Chsetopterus lives in the sand in a large parchment 

 tube, that the intestinal pigiuent can have any function as pigment. 

 On the other hand, it is not unlikely that it may eventually be shown 

 that this green fluorescent 'Cha?topterin' is really representative 

 of the biliverdin of," what the author terms, "vertebrate bile." 



Lankester, from Benham's observations, describes the green gran- 

 ules of the intestinal cells as spherical corpuscles varying in size 

 and embedded in the protoplasm of the epithelial cells. He says 

 they are not dissolved by alcohol entirely, but a colorless oily-looking 

 stroma, quite structureless and translucent, of the same shape as the 

 original colored granule, is left in the body. Dr. Gr. Brandes ('98). 

 on the other hand, regards them as vegetable organisms which live 

 as parasites. He thinks that the "Bonellin" may be identical with 

 the coloring matter of "Chsetopterin" but that the differences may be 

 due to some impurities. If these green granules are symbiotic algae 

 or alg-se in the palmella stage, it should be possible to demonstrate 

 it by means of suital)le nutrient solutions, as was done by Famintzin 

 ('90) and Beyerinck ('90) for symbiosis in Hydra viridis. 



A conspicuous ciliated groove extends within the intestine along 

 its ventral side (Fig. 19), from about the middle of the thirteenth 

 segment (second of the mid-region) till near its posterior end. It is 

 made of tall columnar cells, which contain fewer green granules than 

 the cells of the dorsal and latrral epithelial walls of the intestine. 



